Physostigmine is a compound used medicinally to treat glaucoma; it derives from the Calabar bean, genus Physostigma, so named because the style forms a bladder-shaped hood over the stigma in its flowers; physostegia is a North American perennial herb, the obedient plant or false dragonhead, named in reference to the inflated sepals of its flowers; physalis, a plant of a genus that includes the Cape gooseberry and Chinese lantern, is similarly named; a physoclistous teleost fish (Greek kleistos, closed) is one in which the air bladder is not connected to the alimentary canal, the opposite of physostomous (Greek stoma, mouth).